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Capillary Porosity Depercolation/Repercolation in Hydrating Cement Pastes Via Low-Temperature Calorimetry Measurements and CEMHYD3D Modeling.


pdf icon Capillary Porosity Depercolation/Repercolation in Hydrating Cement Pastes Via Low-Temperature Calorimetry Measurements and CEMHYD3D Modeling. (1327 K)
Bentz, D. P.

Journal of The American Ceramic Society, Vol. 89, No. 8, 2606-2611, August 2006.

Keywords:

cements; calorimetry; porosity; cement paste; temperature; hydration; transport properties; durability; percolation; experiments

Abstract:

Capillary porosity percolation in a hydrating cement paste has a large influence on transport properties and durability. Percolation can be examined using low-temperature calorimetry and using microstructure models. In this paper, the two approaches are compared for cement pastes with different water-to-cement ratios and exposed to various curing conditions. The influence of sealed curing is seen to be particularly important, as cement pastes that initially hydrate to depercolate the capillary pores may later undergo self-desiccation and aging that repercolates them. Model predictions of the degree of hydration and the percolated capillary porosity volume fraction compare favorably with experiments.